oce (version 0.2-1)

oceEdit: Edit an oce object

Description

Edit an element of a oce object

Usage

oceEdit(x, item, value, action,
         reason="", person="", debug=getOption("oceDebug"))

Arguments

x

an oce object. The exact action of oceEdit depends on the class of x; see Details.

item

if supplied, a character string naming an item in the object's metadata (see Details).

value

new value for item, if both supplied.

action

optional character string containing R code to carry out some action on the object.

reason

character string giving the reason for the change.

person

character string giving the name of person making the change.

debug

an integer that specifies a level of debugging, with 0 or less indicating no debugging, and 1 or more indicating debugging.

Value

• An object of class "oce", altered appropriately, and with a log item indicating the nature of the alteration.

Details

There are two ways to use this function.

1. If both an item and value are supplied, then the object's metadata entry named item is updated to the supplied value. 2. If item and value are not supplied, then action must be supplied. This is a character string specifying some action to be performed on the object, e.g. a manipulation of a column. The action must refer to the object as x; see Examples.

3. Applied to an adv object (i.e. data from an acoustic velocimeter), oceEdit treats items named heading, pitch, roll appropriately, depending on the type of adv instrument used. (This is necessary because different manufacturers produce different forms of these items, i.e. Nortek reports them on a time base that is different from the velocity reporting, while Sontek reports them on the same time base.)

In each case, a log entry is stored in the object, to document the change. Indeed, this is the main benefit to using this function, instead of altering the object directly. The log entry will be most useful if it contains a brief note on the reason for the change, and the name of the person doing the work.

Examples

library(oce)
data(ctd)
ctd2 <- oceEdit(ctd, item="latitude", value=47.8879,
                 reason="illustration", person="Dan Kelley")
ctd3 <- oceEdit(ctd, action= "x$data$pressure <- x$data$pressure - 1")